It turns out that TouchID can recognize toes, the ball of your foot, your nose (though it's "very difficult" he says), the heel of your foot ("works better than the thumb, imo,") and even the nipple (though he had trouble getting both the right and the left to register).

But there are limitations. TouchID didn't work with the knee, ankle, belly, earlobes, thigh, or various male body parts located in the nether region. Not surprisingly, at least a handful of men who viewed the post saw it as a challenge, and yes, some reported successfully getting those other body parts to register.

The whole post is hilarious as are the comments from other Reddit users such as: "Whenever I buy a used phone, there are few other things I buy: A new screen, a new battery, and alcohol wipes. Not even kidding."

"I bet a dog's nose would work. Unfortunately, I don't have a dog. And if I did, I wouldn't want him going through my phone, making in-app purchases," another Redditor wrote.

"For science - tongue does not seem to work."

"My husband actually routinely unlocks his iPad with his nose. It started as a joke ("I wonder if this will work?"), but now he says it's very convenient for unlocking the iPad when he has something else in his other hand."

So now you have it, TouchID is multi-body part friendly. Your results may vary.